Sketchfab Forum

Three-point lighting with pbr does not show ambient occlusion on material


(Merlin The Wiz4rd) #1

I was playing around with the PBR shader, but when I assigned the AO map to my material and switched from Environment lighting to a three-point lighting set-up the AO on the material does not seam to exist any more. Turning the channel on and off again does not display any change to the material. Is this a bug or am I doing something wrong?

Picture for clarity:

(Stephomi) #2

You meant that when you selected the lighting preset, the AO channel was disabled?

Hmmm I can't reproduce the bug.
Do you have a consistent way to reproduce the error?

(Merlin The Wiz4rd) #3

The material does not seem to change the appearance when turning the AO on or off with the three-point lighting as it does when I turn it off and on with the environment light turned on.

(Stephomi) #4

@MerlinTheWiz4rd Can you send a link to a model that showcase this issue? (where the materials are already set).

If the model is private you can send it in private.

(Merlin The Wiz4rd) #5

Here it is, The three point lighting is on as well as the AO map is assigned.

(Stephomi) #6

Thanks !

Actually, it makes sense.
Ambient occlusion manages the occlusion of the "ambient" light... so basically the environment.
Ponctuals lights aren't considered as "ambient" so the AO won't have any effects.

However the cavity will occlude everything, the environment, the lights and even the emissive.

(Thanks @paul_sketch for the reminder, I complety forgot about that -_-)

(Merlin The Wiz4rd) #7

Ok, thanks for the explanation!